Half of new HIV infections in the United States are among African-Americans. After decades of research focused on individual factors, investigators have concluded that individual behaviors are insufficient to explain the racial disparity in HIV rates. As a result, researchers have turned to focus on social factors that influence HIV risk behaviors. Incarceration is one such factor that disproportionately affects the health of African American individuals, families, and communities, and is associated with HIV infection. Multiple theories have been proposed about the association between incarceration rates and HIV rates. To test one proposed explanation for the association, the applicant will conduct a community-based survey in African American communities in Baltimore, Maryland. More than half of young African-American men in Baltimore are incarcerated or otherwise involved in the criminal justice system, and the metropolitan area has the fifth highest HIV rate in the nation. The incarceration of African-American males makes male partners scarce, and concurrent sexual partnerships with multiple females may become normal for many men. The perception that few male partners are available may promote the belief that men have more power than women in sexual relationships, resulting in less condom use and HIV infection. The study specifically aims to: 1) develop and validate scales to measure social norms about engaging in concurrent sexual partnerships;2) assess whether psychosocial factors (norms about concurrent partnerships, perception of partner availability, and relationship power) are associated with behavioral risk factors for HIV, such as condom use and concurrent sexual partnerships;and 3 )assess whether these psychosocial factors explain the relationship between incarceration and HIV infection. Male and female adults will be recruited from high- poverty, high-AIDS prevalence areas in Baltimore as part of the CDC National HIV Behavioral Surveillance System study of heterosexuals at high risk of HIV infection. Participants will be tested for HIV, and a standardized questionnaire will collect information from 750 participants about sexual activity, drug use, incarceration status, and other behavioral and partner characteristics. The scale measuring social norms about engaging in concurrent sexual partnerships will be developed in a pilot study in the Baltimore City STD Clinics. National research priorities support research dedicated to understanding the social context of sexual risk behaviors. Identifying how social factors can impact HIV rates will allow for prevention programs that can alter the social environment and ultimately individual HIV risk.